Male piglets were fed the eperimental diet (1.5% cholesterol) by their mothers for a period of 5 weeks. Serum cholesterol, lipoproteins, phospholipid, liver microsomal HMG-CoA reductase, cholesterol 7 alpha-hydroxylase, fatty acid synthetase, microsomal cholesterol accumulation and analysis of milk and diet were carried out. Results are presented only for animals on experimental diet from birth to 5 weeks of age and on control diet thereafter. Increase in body weight from birth till 16 weeks of age is normal. An 8 fold increase in serum cholesterol level was observed in lactating mothers within 5 weeks on high cholesterol -high fat diet. Analysis of milk did not show any increase in cholesterol content in spite of high cholesterol - high fat diet though level is about 10 fold higher than reported values. A 3 fold increase in serum cholesterol level was observed in male piglets during suckling period. LDL and HDL fractionation of lipoprotein also showed at least two fold increase in cholesterol content during this period. HMG-CoA reductase, cholesterol 7 alpha-hydroxylase, fatty acid synthetase and microsomal cholesterol level was also analyzed in 5 week old pigs and reported.